1 #include<cstdio> 2 #include<iostream> 3 #include<cstring> 4 #define M 10000 5 #define inf 2139062143 6 using namespace std; 7 int cnt=1,n,m,s,ans,T,d[M],q[2*M],f[M],head[M],next[10*M],u[10*M],v[10*M],w[10*M],fro[10*M],fr[M]; 8 void jia1(int a1,int a2,int a3,int a4) 9 { 10 cnt++; 11 next[cnt]=head[a1]; 12 head[a1]=cnt; 13 fro[cnt]=a1; 14 u[cnt]=a2; 15 v[cnt]=a3; 16 w[cnt]=a4; 17 } 18 void jia(int a1,int a2,int a3,int a4) 19 { 20 jia1(a1,a2,a3,a4); 21 jia1(a2,a1,0,-a4); 22 return; 23 } 24 bool spfa() 25 { 26 memset(d,127,sizeof(int)*(T+1)); 27 memset(fr,0,sizeof(int)*(T+1)); 28 memset(f,0,sizeof(int)*(T+1)); 29 d[0]=0; 30 f[0]=1; 31 q[1]=0; 32 int h=0,t=1; 33 for(;h<t;) 34 { 35 h++; 36 int p=q[h]; 37 f[p]=0; 38 for(int i=head[p];i;i=next[i]) 39 if(v[i]&&d[u[i]]>d[p]+w[i]) 40 { 41 d[u[i]]=d[p]+w[i]; 42 fr[u[i]]=i; 43 if(!f[u[i]]) 44 { 45 f[u[i]]=1; 46 t++; 47 q[t]=u[i]; 48 } 49 } 50 } 51 if(d[T]!=inf) 52 return 1; 53 return 0; 54 } 55 void mcf() 56 { 57 int mx=inf; 58 for(int i=fr[T];i;i=fr[fro[i]]) 59 mx=min(mx,v[i]); 60 for(int i=fr[T];i;i=fr[fro[i]]) 61 { 62 v[i]-=mx; 63 v[i^1]+=mx; 64 ans+=mx*w[i]; 65 } 66 return; 67 } 68 int main() 69 { 70 scanf("%d%d%d",&n,&m,&s); 71 T=n+1; 72 for(int i=1;i<=n;i++) 73 { 74 int a1; 75 if(i!=n) 76 jia(i,i+1,s,m); 77 scanf("%d",&a1); 78 jia(i,T,a1,0); 79 } 80 for(int i=1;i<=n;i++) 81 { 82 int a1; 83 scanf("%d",&a1); 84 jia(0,i,inf,a1); 85 } 86 for(;spfa();) 87 mcf(); 88 printf("%d\n",ans); 89 return 0; 90 } 91
网络流
